[olakara]

Hi all,

I am using Equinox to run my OSGi bundle. The bundle runs a thread for indefinite time. At certain point of time, I may need to stop the bundle. The problem I face is that, i am not able to stop the bundle!! When I issue the stop command on the OSGi console.. I get the following error:

org.osgi.framework.BundleException: State change in progress for bundle file:I:\OSGiRuntime\Equinox\custom\ThreadBundle.jar" by t
hread "main".
at org.eclipse.osgi.framework.internal.core.AbstractBundle.beginStateChange(AbstractBundle.java:1144)
at org.eclipse.osgi.framework.internal.core.AbstractBundle.stop(AbstractBundle.java:428)
at org.eclipse.osgi.framework.internal.core.AbstractBundle.stop(AbstractBundle.java:422)
at org.eclipse.osgi.framework.internal.core.FrameworkCommandProvider._stop(FrameworkCommandProvider.java:285)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.osgi.framework.internal.core.FrameworkCommandInterpreter.execute(FrameworkCommandInterpreter.java:150)
at org.eclipse.osgi.framework.internal.core.FrameworkConsole.docommand(FrameworkConsole.java:302)
at org.eclipse.osgi.framework.internal.core.FrameworkConsole.console(FrameworkConsole.java:287)
at org.eclipse.osgi.framework.internal.core.FrameworkConsole.run(FrameworkConsole.java:223)
at java.lang.Thread.run(Unknown Source)
Caused by: org.eclipse.osgi.framework.internal.core.AbstractBundle$BundleStatusException
... 13 more

Here is my bundle's code:

package threadbundle;


import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;

public class Activator implements BundleActivator {

	private Thread myThread;
	private CustomThread cTObject;
	
	public void start(BundleContext context) throws Exception {
		System.out.println("Starting ThreadBundle...");
		cTObject = new CustomThread();
		myThread = new Thread(cTObject);
		myThread.run();
	}
	
	public void stop(BundleContext context) throws Exception {
		if(myThread.isAlive())
			cTObject.stopTheThread();
		System.out.println("Stopping thread bundle..");
	}
	
	private class CustomThread implements Runnable {

		boolean stopper;
		
		CustomThread() {
			stopper = false;
		}
		
		public void stopTheThread(){
			if(!stopper)
				stopper = true;
		}
		
		public void run() {
			try {
				while(!stopper) {
					System.out.println("Message from thread...");
					Thread.sleep(5000);
				}
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
			
		}
	}

}

Anybody know how to solve this?
Thanks in advance,
Abdel Olakara.
Techno Paper

[mcculls]

Shouldn't that be myThread.start() not myThread.run() ?

myThread.run() means you're not actually starting the thread, but running your task in the current thread from the OSGi framework - this is why the framework thinks your bundle is still starting, because it never exits the start method.

[olakara]

Hi,
I tried starting the bundle by calling myThread.start().. i noticed that, the state of the bundle to not change from STARTING to ACTIVE :-(

Originally Posted by mcculls

Shouldn't that be myThread.start() not myThread.run() ?

myThread.run() means you're not actually starting the thread, but running your task in the current thread from the OSGi framework - this is why the framework thinks your bundle is still starting, because it never exits the start method.

[mcculls]

Originally Posted by olakara

Hi,
I tried starting the bundle by calling myThread.start().. i noticed that, the state of the bundle to not change from STARTING to ACTIVE :-(

Sorry, perhaps I wasn't clear enough - in the code you posted you are using the myThread.run() method, which simply executes your runnable code in the current thread (ie. the framework thread calling your bundle start method). This means your bundle state will stay as STARTING, because your bundle start method never returns (you can add a println to show this).

If you change this to be myThread.start() then the JVM will execute your runnable code in a new Java thread separate to the framework thread, and your start method will return as expected (for more background on starting threads, see the javadoc for Thread.start() compared to Thread.run()).

I've just tested this change locally on Equinox and Felix (another OSGi framework) and can start and stop your example bundle without error.

Here's the working code, where I've only changed one line:

package threadbundle;

import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;

public class Activator implements BundleActivator {

	private Thread myThread;
	private CustomThread cTObject;
	
	public void start(BundleContext context) throws Exception {
		System.out.println("Starting ThreadBundle...");
		cTObject = new CustomThread();
		myThread = new Thread(cTObject);
		myThread.start(); // !! use start() to fork a new thread !!
	}
	
	public void stop(BundleContext context) throws Exception {
		if(myThread.isAlive())
			cTObject.stopTheThread();
		System.out.println("Stopping thread bundle..");
	}
	
	private class CustomThread implements Runnable {

		boolean stopper;
		
		CustomThread() {
			stopper = false;
		}
		
		public void stopTheThread(){
			if(!stopper)
				stopper = true;
		}
		
		public void run() {
			try {
				while(!stopper) {
					System.out.println("Message from thread...");
					Thread.sleep(5000);
				}
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
			
		}
	}
}

You might want to check that you're definitely deploying the new version of the code - have you restarted the framework, or just updated the bundle? If you updated it, what commands did you use? BTW, if all else fails you could always clear out the bundle cache and do a fresh deployment with the new code, if you're not sure which version you're running...

[olakara]

hi
thanks, it worked. the problem was the jar didn't get updated. And was able to fix it by the time i got your reply. Thanks for the explanation.

Regards,
Abdel Olakara

[cghersi]

Hi all, I'm facing quite the same problem:
I'm able to correctly stop the bundle, but the thread continues to run also if I call a stopThread() method in my thread class the does the following:

		Thread ghost = this.myThread;
		this.myThread=null;
		ghost.interrupt();

how may I be sure to stop the thread?

thank you very much!